Transmission especially for automobile vehicle

ABSTRACT

1,190,088. Epicyclic change-speed gear. SOC. ANON. FRANCAISE DU FERODO. 18 Aug., 1967 [19 Aug., 1966; 26 July, 1967], No. 38135/67. Heading F2D. In a change-speed gear, particularly for automobile vehicles, wherein a four (A-D) element epicyclic gear, having the element C permanently connected to an output 11, provides one Reverse ratio, by coupling the element A to an input 10 and braking the element B, and three Forward ratios, viz.: Low Forward, by coupling the element A to input and braking the element D; Intermediate Forward, by coupling the element B to input and braking the element D; and High Forward, by coupling both the elements A, B to input, the element A is coupled to input via an auxiliary change-speed gear providing subratios in Reverse and Low and High Forward, thus providing, through the whole arrangement, N Reverse ratios and 2N+1 Forward ratios, where N is the number of ratios provided in the auxiliary gear. Auxiliary gear upshift results in upshifts in Reverse and Low Forward but a downshift in High Forward. Where the arrangement permits, a further ratio (overdrive) may be provided by coupling the element B to input and braking the element A. In Fig. 1, the epicyclic gear comprises two sun-ring trains compounded, the elements A, D being comprised by first and second train suns 17, 17&lt;SP&gt;1&lt;/SP&gt; respectively, the element B comprising the first train carrier 19 and the second train ring 18&lt;SP&gt;1&lt;/SP&gt;, and the element C comprising the first train ring 18 and the second train carrier 19&lt;SP&gt;1&lt;/SP&gt;. The element B may be coupled to the input shaft 10 through gears 21, 22, 24, 25 and a clutch M and braked at Far; the element C is fast with the output shaft 11; and the element D may be braked at F av . The auxiliary gear provides two ratios between the input shaft 10 and the element A, viz.: reduction, through gears 21, 22, 27, 28 and a clutch S 1  and direct, through a clutch S 2 . In Fig. 2 (not shown), the input shaft is constituted by the shaft, 23. carrying gears 22, 27, 24. In Fig. 3 (not shown), a brake (F sh ) for the element A (providing overdrive) is housed in a casing partition between the gears 28, 25. In Figs. 4, 5 (not shown), the auxiliary gear respectively provides three and four ratios each ratio being brought in by a corresponding clutch. In Fig. 6 (not shown), the change-speed gear includes a tworatio auxiliary gear and is serially preceded by a fluid coupling or, as described, an hydrodynamic torque converter disposed parallel to the epicyclic gear axis and having a reactor reacting on a one-way detent. The clutch S 1  comprises a small capacity clutch in parallel with a one-way clutch. The clutch S 2  is hydraulically actuated and housed in the converter bell. The brake F av comprises a small capacity brake in parallel with a releasable one-way brake. The output shaft 11 may be stationed by a positive Park lock (65). In Fig. 7, the change-speed gear is serially preceded by an hydrodynamic torque converter 42 and includes a two-ratio auxiliary gear. The epicyclic gear elements A, D are comprised by suns 66, 68 respectively, the element B by a ring 70, and the element C by a carrier geared at 78, 79 to the output shaft and carrying intermeshed planets 67, 69 respectively meshing the sun 66 and the sun and ring 68, 70. The clutch S 1  is housed in the converter bell and comprises a small capacity clutch in parallel with a one-way clutch 77. A positive Park lock is operative on the carrier C. In Fig. 8 (not shown) the arrangement is similar to that of Fig. 7, but inter alia, the carrier is fast on the output shaft and the converter is disposed parallel to the epicyclic gear axis.

p 1970 P. A. cs. LEPELLETIER 3,505,905

TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE FiledAug- 5, 1967 v 5 Sheets-Sheet,1

N F, n I (9 N Q I FIG] firm: Awe: Gian-is ZEPELLET/EK April 14, 1970 Filed Aug. 5, 1967 P. A. G. LEPELLETIER TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE 5 Sheets-Sheet 2 April 14, 1970 P. A. G. LEPELLETIER 3,505,905

TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE Filed Aug. 5, 1967 5 Sheets-Sheet 5 01 Q" J F 1' 3 L J II A \r a Q ZEPELLET/ER 5 w April 1970 P. A. G. LEPELLEIIER TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE Filed Aug. 5, 1967 5 sheets-Sheet 4 [WI mime I Pa e: fl/vbks $5 2625 m PM A ril 14, 1970 P. A. c5. LE PELLETIER 3, 5

TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE Filed Aug. 5, 1967 s Sh'eets-Sho s (0h LOU) United States Patent 3,505,905 TRANSMISSION ESPECIALLY FOR AUTOMOBILE VEHICLE Pierre Andr Georges Lepelletier, Chatou, France, as-

signor to Societe Anonyme Fraucaise du Ferodo, Paris, France, a corporation of France Filed Aug. 3, 1967, Ser. No. 658,230 Claims priority, application France, Aug. 16, 1966, 73,509; July 26, 1967, 115,688 Int. Cl. F16h 47/08 US. Cl. 74-688 5 Claims ABSTRACT OF THE DISCLOSURE A known planetary gear train has four elements, the first of which may be free or coupled to the input, the second of which may be free or coupled or immobilized, the third of which is permanently connected to the output, and the fourth of which may be free or immobilized. This known gear train is improved by inserting, between the input and the first element, a ratio-varying means in the form of at least two selectively engagea-ble clutches of different driving ratios. This does not modify the middle forward drive, but modifies in the same direction the reverse and low forward drives, and modifies in the opposite direction the high forward drive.

The present invention relates to a transmission system, especially for automobile vehicles, of the general type comprising a fixed gear-box casing or frame, movement input, a movement output, and a planetary gear-train having four elements of the type including a first element adapted either to be coupled to the movement input or to be free; a second element, adapted either to be coupled to the movementinput or immobilized on the frame, or free; a third element, permanently coupled to the movement output; and a fourth element adapted either to be immobilized on the frame, or to be free; whereby: for a reversing condition, the first element is coupled to the movement input, the second element is immobilized and the fourth element is free; for a low forward running condition, the first element is coupled to the movement input, the second element is free and the fourth element is immobilized; for a middle condition of forward running, the first element is free, the second element is coupled to the movement input, and the fourth element is immobilized; and for a high condition of forward running, the first and second elements are coupled to the movement input and the fourth element is free.

It will be noted that the conditions of the gear train, both on reverse running and on forward running, are intrinsic conditions, that is to say they are inherent and proper to the'train. The three conditions of forward running are termed low, middle and high so as to correspond to the gear ratios, the term middle being adopted so as to indicate that the corresponding condition is comprised between the low and the high conditions.

The invention has for its object 'a transmission system of the type indicated above, which makes is possible to obtain a greater choice of gear ratios, both on reverse running and on forward running.

The invention is especially characterized in that the coupling means of the second element with the movement input has a ratio which is fixed and pre-determined and makes it possible to obtain a forward ratio, known as the middle ratio, while the coupling means of the first element with the movement input comprises ratio-varying means, which has the effect of varying, on the one hand 3,505,905 Patented Apr. 14, 1970 in the same direction, the ratio on reverse running and the ratio of low forward speed and on the other hand, in the reverse direction, the forward high-gear ratio.

In one form of embodiment of the invention, the coupling for the first element has a plurality of alternative power paths, for example two, three, four, or more generally N paths, having different ratios, while the varying means comprise means for selecting one of the N paths, which gives N reverse ratios and 2N +1 forward ratios.

When required, the first element may in addition be made immobilizable on the frame in order to obtain a supplementary or overdrive forward ratio forming the 2N +2 forward ratio, for which the first element is immobilized, the second element is coupled to the movement take-off, and the fourth element is free.

The transmission according to the invention has considerable advantages, especially in automobile applications.

The necessary number of releasable coupling and immobilization means is very small and is equal to N +3 without overdrive and N+4 with overdrive, namely N releasable coupling means corresponding to the N power paths of the first element coupling, a releasable coupling means 'allotted to the middle path, two releasable immobilizing means allotted respectively to the second element for reverse gears and to the fourth element for the low and middle forward gears, and if there is an overdrive. a releasable immobilization means allotted to the first element.

In addition, the changing-up and changing-down of the N ratios on reverse running and of the 2N+l (or 2N+2 in case of overdrive) forward ratios is effected merely by operating, for each change, two simultaneously releasable means, thus providing an easy control which is free from any discontinuity.

It will also be observed that the kinetic energy stored in the rotating members of the transmission is small on each of the forward or reversing ratios, which permits of convenient construction and gives an excellent efficiency.

In addition, the spacing of the ratios may be arranged in such manner as to be appropriate to various fields of application, and in particular to automobile applications. By way of example and without any implied limitation, it is possible to obtain forward ratios such as: first, 0.372; second, 0.556; third, 0.792; fourth, 1.074; and fifth, 1.295, which constitutes a well-spaced range giving remarkable performances from automobile vehicles, together with reverse-running ratios such as: first, 0.444; second, 0.665; which are also perfectly adapted.

Forms of embodiment of the invention are described below by way of example, reference being made to the accompanying drawings, in which:

FIG. 1 is a diagrammatic view of a transmission according to the invention, permitting the provision of five forward ratios and two reversing ratios;

FIG. 2 relates to an alternative form, in which the movement input has its axis parallel to and not coincident with the axis of the planetary gear train;

FIG. 3 shows another alternative form permitting an additional ratio or over-drive ratio to be obtained on forward running;

FIG. 4 is a partial view similar to that of FIG. 1, but relates to a transmission permitting the provision of seven forward-running ratios and three reverse ratios;

FIG. 5 is a partial view similar to that of FIG. 4, but relates to a transmission which can provide nine forward ratios and four reverse ratios;

FIG. 6 is a view of a transmission according to the invention, in which the movement input is constituted by the turbine of a hydraulic torque converter;

FIGS. 7 and 8 are similar to FIG. 6, but are respec- A clutch M, the middle gear clutch, interposed between tively concerned with two further alternative forms. the sleeve 26 and the element B and permitting, when Reference will first be made to FIG. 1, in which a engaged, the path V to be put in use, and, when distransmission, especially for an automobile vehicle, comengaged, the path V is put out of use. prises a movement input shaft 10 and an output shaft 11, The coupling means of the element A with the movewhich in this case are coaxial. The fixed gear-box or frame ment input comprise a first element coupling V having box 12 containing the transmission is divided into two ada variable nature and comprising ratio-varying means. jacent compartments 13 and 14, separated by a parti- The reproductive channel V is amultiple channel comtion 15. prising a plurality of branches, in this case two. One of A planetary gear train 16 is housed in the compartment 10 the paths comprises the pinions 21 and 22, a pinion 27 and is of the general type having four elements A, B, fixed to the shaft 23, a pinion 28 engaging with the pinion C and D, with complete couplings, in which the angular 27, and a clutch S interposed between the pinion 28 and speeds of all the elements are defined when the speeds a h ft 29 rigidly fix d to the el m nt A. of any two of them are given. The other path comprises a further clutch S directly In the non-limitative example given in FIG. 1, the interposed between the shaft 10 and the shaft 29. planetary gear comprises two simple identical planetary Th l t he S and S fo ratio-varying m an of p r i each having a sun g a g g r and a pl the coupling V and when either the one or the other is carrier, Coupled together in a symmetrical manner y the engaged, permit this coupling to have either a ratio other planet carrier of one being fixed to the ring gear of the than unity, determined by the pinions 21, 22, 27 and 28, other and vice-versa. or the ratio unity. The clutches S and S enable the Afirst simple planetary portion comprises a sun gear 17, li V to b t t f operation h th are a ring gear 18, a planet carrier 19 and planet gears 20. b h disengaged, The second simple Planetary Portion Comprises a sun gear There will now be considered the immobilization means 17', a ring gear 18', a p a et ca r er and Planets of the immobilizable elements, that is to say the elements The ring gear 18 and the planet carrier 19' are rigidly B d D, fixed 110 each other, While the ring gear 18' and the planet These means comprise a brake F co-operating with C e are fixed he the elements B so as to immobilize it for the purpose of T e l elements D of the p 'y gear the reverse gears, and a brake F co-operating with the train 16 thus affangsd are in this Cash P in the element D so as to immobilize it for the purpose of the lowing manner: 30 low and middle forward gears.

The first element A is constituted by 17. The second As can be Seen f o FIG 1, h compartment 13 f element B is formed y The third fileliheflt C is the frame 12 receives the planetary gear train A, B, C, D, constituted by 18, 19', and the fourth element B 13 formed the brakes Far d P h iddl gear l h M d h by 17'. pinions 24, 25, while the other compartment 14 of the The fi st element A is adapted either to be coupled to frame 12 receives the clutches s and s and the gear movement input 10 freewheel systems 21, 22 and 27, 28.

T Second element B is adapted either to be coupled The transmission thus constituted has one reversing cont0 the movemant input 10, immobilized on the frame dition and three forward conditions known respectively as 12, or free. the low, middle and high conditions.

Th third element C is Permanently coupled to the 40 In addition, the transmission has a neutral point, for put shaft 11. which the elements A, B and D, or at least two of these,

The fourth element D is adapted either to be immob1lare released at the same time iZed on P 12, free; The sub-division of the coupling V into two paths has Conslderauon W111 first glven to the couphng means the effect of doubling the reverse condition, the low forof the elements A and B with the movement input 10.

Beginning with the element B, it can be seen from FIG. 1 that the coupling means of the element B with 323$; s gzi g ig ggiggfig z g gg fia iggfi gfifiggg that is to say five forward gears, in accordance with the ratio. following table, in which the sign lndicates that one Going from the input 10 to the element B, the middle Clutch brake is g While the slgn indicates path V comprises: that it is released.

ward condition and the high forward condition, which gives in all two reversing ratios, two low forward ratios, one forward middle ratio and two high forward ratios,

TABLE (FIG. 1)

Middle L f d f d H hi (1 iiiifiit n mg Neutral fi ndii i coiii iiicn ifmdiii fi A Coupled to 10 Free Coupl d t0 0- Free Coupled to 10.

' F C 1 d1; 10 D TSIII: l fi ih gk il f gg Izilii lobilized lltiihlgiliz dnu Free.

1st 2nd 151: 2nd 3rd forward 4th 5th reverse reverse Neutral forward forward middle forward forward g i i as it it 3 E it J A pinion 21 fixed on the shaft 10 and engaging with a It will be noted that P is engaged for all the low and pinion 22 fixed on a countershaft 23 parallel to the middle forward speeds, but is released for the high forward speeds. shaft It should be observed that the change of ratio of the P Ph rigidly fixed to the shaft fingaging coupling V obtained by releasing S assumed to be first with a pawn 25 fixed on a sleeve 26 which 1s free for engaged, d b engaging S assumed to b fir t l d, rotation; results in a change-up from 1st to 2nd in reverse, a change- 6 up from 1st to 2nd in low forward gear, and a change- The overdrive which, in the case of the application to down from th to 4th in top forward gear. FIG. 1 forms a sixth forward gear, is obtained with the Good results have been obtained with the following following conditions of engagement and release of the numbers of teeth on the various pinions and toothed various brakes and clutches: wheels. 5

Teeth M u; Sun gear 17 26 Ring gear 18 54 2 Planet carrier 19 14 ar Sun gear 17' 26 av Ring gear 18' 54 51 Planet carrier 19' 14 pinions: In the case of the application to FIG. 1, the overdrive 21 31 atio is 1.321 and in that of the application to FIG. 2, it 22 is 1.705. 38 It should be noted that the overdrive ratio of FIG. 3 25 33 may be applied not only to the cases of FIG. 1 and FIG. 3;

2, but also to all cases of the other figures.

Reference will now be made to FIG. 4, in which the arrangement is similar to that which has been described with reference to FIG. 1, but in which the coupling V 20 The gear ratios are then as follows:

Reverse Forward has three paths comprising respectively three clutches S S and S making 1t posslble to trlple the condition of gig 838% reverse, the low forward condition and the high forward 8.2% condition, whlch gives in all three reverse, three low for- L078 Ward, one middle forward and three high forward ratios, that is to say seven forward ratios, to which there may be added an overdrive if so required, forming the eighth Reference F l 9 be made FIG in Which the forward gear by virtue of the addition of a supplementary arrangement is simllar to that which has been described brake Such as the brake Fsh of with reference to FIG. 1, but in which the movement input one of the three paths of the coupling VP comprises shaft is constituted by the shaft 23, while the shaft 10 a pinion 30 fixed on the Shaft 10 and engaging with a serves as a countershaft. The various preceding; ratios are pinion 31 fixed to a countershaft 32 and couplable by the all staggered, taking account of the multiplication due to 3 clutch S1 with a pinion 33 which in tum engages with a the pll'llOIlS 22 and 21, that is to say in the proportion of pinion 34 rigidly fixed to the Shaft 29' to A second path of the coupling V comprises the clutch The followlng gear ratlos are then obtamed: S directly interposed between the shaft 10 and the shaft 29. The third path of the coupling V comprises the 40 pinions 2'1 and 22, the shaft 23 and the clutch S inter- 0.314 0. 63 posed between the shaft 23 and a pinion 35 which engages Reverse Forward i 3; $3; with a pinion 36 fixed to the shaft 29.

1.081 The following table indicates the diagram of operation 390 of the transmission of FIG. 4.

TABLE (FIG. 4)

Middle forward Reverse running condition Neutral Low forward condition condition High forward condition F C l d t 10. %111111111i"%%%ii%5?1 "no... F H eti'i ie o 10. 1%.? D Free lmmobihzedut. Free.

4th forward 3rd rev. Neutral 1st ford 2ndford 3rd iord middle 5th ford 6th ford 7th Iord i M at at at it it it it it It should be observed that the alternative case of FIG. 2 It will be noted that F is engaged for all the low and Can b applied t only t th case f FIG, 1, but l to middle forward speeds, but is released for the high forall those of the other figures. Ward p Reference will now be made to FIG 3 in which, in Good results have been obtained-with the same planetary addition to the possibility of its drive by either of the ggar as that 1, and Wlth the followlng number of clutches S and S and its possibility of release by disi h Pmlonsh engagement of the two clutches S and S the first element 50 A has been provided so as to be immobilized on the frame 12 in order to obtaln an additional ratio, known as the 24 34 forward overdrive ratio, for which the element A is 25 37 immobilized, the element B is coupled to the movement 70 30 31 input and the element D is free. 31 4 To this end, a brake F is associated with the shaft 29 33 28 rigidly fixed to the element A, and is housed in the parti- 34 43 tion 15 which separates the compartments 13 and 14 of 35 38 the gear-box 12. 36 33 The following gear ratios are then obtained:

Reverse Forward 0. 243 0. 204 0. 482 0. 403 0.715 0. 59s 0.800 1. 040 Sixth 1. 273 Seventh 1. 512

When an overdrive is provided, its ratio is 1.755.

When the movement input is formed by the shaft 23 instead of the shaft 10, the various ratios given above are all staggered, taking account of the step-down ratio due to the pinions 22 and 21, that is to say in the proportion of 31 to 40.

In the alternative form of FIG. 5, the arrangement is again similar to that which has been previously described, but the coupling V now has four branches comprising respectively four clutches S S S and S making it possible to quadruple the condition of reverse, the low forward condition and the high-forward condition, which gives in all four reverse, four low forward, one middle forward, and four high forward gears, that is to say nine forward gears, to which there may if so desired, be added an overdrive forming a tenth forward gear, by virtue of the addition of a supplementary brake such as the brake F of FIG. 3.

One of the four arms of the coupling V comprises the pinions 30, 31, the shaft 32, the clutch S and the pinions 33, 34.

A second branch of the coupling V comprises the pinions 30, 31, the shaft 32, the clutch S and a pinion 37 engaging with a pinion 38 fixed on the shaft 29.

A third branch of the coupling V comprises the pinions 21, 22, the shaft 23, the clutch S and the pinions 35 and 36.

The fourth branch of the coupling V comprises the pinions 21, 22, the shaft 23, the clutch S and a pinion 39 engaging with a pinion 40 rigidly fixed to the shaft 29.

The following table indicates the diagram of operation of the transmission shown in FIG. 5.

When an overdrive is provided, its ratio is 2,200.

When the movement input is constituted by the shaft 23 instead of the shaft 10, the various ratios given above are all staggered, taking account of the step-down ratio due to the pinions 22 and 21, that is to say in the proportion of 31 to 40.

It will be understood that a drive of any appropriate type, associated with the transmission for actuating the various operating members, namely M, S S S S F and P in the case of FIG. 5, and where applicable F in the case of FIG. 3, may be provided either so as to make it possible to obtain the whole of the possible ratios, in the present case four reverse and nine or ten forward ratios, or so as to obtain part only, considered sufficient for the application contemplated, of the possible ratios. This observation is applicable not only to FIG. 5, but also to all the other forms of embodiment described and/r contemplated.

Reference will now be made to FIG. 6 which concerns a transmission with two reverse gears and five forward gears as in FIG. 1, but in which the movement input 10 is constituted by the turbine 41 of a hydrokinetic coupling apparatus 42, such as a hydraulic torque converter or coupler, in this case a converter, of which the impeller is seen at 43 and at 44 the reactor coupled to the fixed frame 12 by a free-Wheel 45. Hydraulic torque converters TAB LE (FIG.

Middle ford Reverse running conditions Neutral Low forward condition cond'n High forward condition A Coupled to Free Coupled to 10 Free Coupled to 10.

B Immobilized ..do Free Coupldd to 10-.. Do.

D Free don--- Immobilized Immoblized..... Free.

181; 2nd 3rd 4th 1st 2nd 3rd 4th 5th middle 6th 7th 8th 9th rev. rev. rev. rev. Neutral ford iord tord ford ford tord ford Iord ford It should be observed that F is engaged for all the low and middle forward speeds, but is released for the high forward gears.

Good results have been obtained with the same planetary gearing as that of FIG. 1, and with the following numbers of teeth on the pinions.

or couplers of the type of FIGS. 6-8 are shown and described in greater detail in US. Patent No. 3,213,988, Oct. 26, 1965.

The middle power path V comprises a central shaft 46 permanently fixed to the turbine 10, the clutch M, a shaft 47 surrounding the shaft 46 and a pinion 48 fixed to the shaft 47 and engaging with a pinion 49 rigidly fixed to the second element B.

The coupling V has two paths. One of the paths comprises the shaft 46, the clutch S a shaft 50, concentric with the shafts 46 and 47, and a pinion 51 fixed to the shaft 50 and engaging with a pinion 52 fixed on the first element A. It will be seen from FIG. 6 that the clutch S is madeup of a clutch 53 of small capacity connected in parallel with a free-wheel 54. The other path V comprises the clutch S which is housed in the same bell 55 filled with oil as the converter 42, and is composed of a pair of plates 56 and 57 in cylinder-piston relation, fast for rotation with the turbine 41 and with a friction disc 58 fixed for rotation with a shaft 59. The latter surrounds the shaft 46 and carries a pinion 60 which engages with a pinion 61 fixed to the first element A.

There is provided at P the reversing brake which cooperates in the first and second reverse gears with the second element B, and which in this case is applied to the shaft 47 and there can be seen at F the forward-running brake which co-operates in the first, second and third forward gears with the second element B, and which in this case consists of a small capacity brake 62 connected in parallel with a free-wheel 63 which is coupled to the frame 12 by a clutch 64.

In addition, there is seen at 65 a parking finger by means of which the output shaft 11 can be locked.

The planetary gear system A, B, C, and D has the same arrangement as that of FIG. 1, with wheels and pinions having the same number of teeth, the elements C and D being the corresponding third and fourth elements, respectively.

The other pinions have the following numbers of teeth.

Pinions: Teeth There are then obtained the following gear ratios:

Reverse Forward Third 0. 793

Fifth 1.295

It will be noted that the special construction of S by means of a clutch of small capacity and'a free-wheel coupled in parallel, excludes in this case the introduction of a sixth gear by an overdrive brake, which necessitates the complete release of the channel S not'obtained by reason of the choice of the free-wheel.

Reference will now be made to FIG. 7, in which the arrangement is similar to that of FIG. 6 with a hydraulic torque converter 42, and also makes it possible to obtain two reversing gear ratios and five forward ratios.

The planetary gear train A, B, C, D is of the same general type as that of FIG. 1, but has a different arrangement and comprises two sets of planets engaging with each other. The element A is a sun gear 66 which engages with planet 67, while the element D is a further sun gear 68 which engages with another planet 69. The two planets 67 and 69 are carried by the element C acting as a planet carrier and engaging with each other. The element B is a ring-gear 70 which engages with the planet 69.

The middle path V comprises the central shaft 46 which is permanently fixed to the turbine 41, the clutch M, and a shaft 71 fixed to the element B.

The coupling V has two paths. One of the paths comprises the clutch S a shaft 72 carrying a pinion 73 which engages with a pinion 74, the latter being rigidly fixed to another pinion 75. The set of pinions 74 and 75 is for example mounted freely around the shaft 11. The pinion 75 engages with a pinion 76 fixed to the element A. It will be noted from FIG. 7 that the clutch S is housed in the bell 55 filled with oil, with a construction similar to that of the clutch 56, 57 and 58 of FIG. 6. In this case, the clutch S is composed of the clutch 56, 57 and 58 which is provided in FIG. 7 with a small capacity and which is connected in parallel with a free-wheel 77.

The other path of the coupling V comprises the clutch S interposed directly between the shaft 46 and the element A. There is recognized at P the reverse running brake associated with the element B, at F the forward brake associated with the element D, and at 65 the parking finger. It will be seen that the output shaft 11 is mounted parallel to the axis of the planetary gearing A, B, C, D and is coupled to the element C by a pair of pinions 78 and 79.

Good results have been obtained with the following numbers of teeth on the various pinions.-

Teeth Sun gear 66 28 Planet carrier 68 23 Ring gear 70 79 Pinions:

The following gear ratios were then obtained:

Reverse Forward Fifth 1.182

Reference will now be made to FIG. 8, in which the arrangement is similar to that of FIG. 6 or FIG. 7, with a hydraulic torque converted 42, and also enables two reverse ratios and five forward ratios to be obtained.

The planetary gear system A, B, C, D is of the same general type as that of FIG. 1, and has an arrangement similar to that of FIG. 7, with two sets of planets 67 and 69 in engagement with each other. The element A is the sun gear 66 which engages with the planet 67, while the element D is the sun gear 68 which engages with the planet 69. The two planets 67 and 69 are mounted on the element C acting as a planet carrier, and engage with each other. The element B is the ring gear 70 which engages with the planet 69.

The middle path V comprises the central shaft 46 permanently fixed to the turbine 41, a pair of pinions 80 and 81, a shaft 82, the clutch M and a shaft 83 rigidly fixed to the element B.

The coupling V has two paths. One of the paths comprises the clutch S a shaft 84, a pair of pinions 85 and 86, and a shaft 87 fixed to the element A. It will be seen from FIG. 8 that, as in FIG. 7, the clutch S is housed in the bell 55 and is composed of the clutch 56, 57, 58 of small capacity, mounted in parallel with the free wheel 77.

The other path V comprises the clutch S interposed between the shaft 82 and the shaft 87 fixed to the element A. There is again seen at F, the reverse-running brake associated with the element B, at F the forwardrunning brake associated with the element D, and at 65 the parking finger.

Good results have been obtained with the following numbers of teeth on the various pinions.

Teeth Sun gear 66 28 Planet carrier 68 23 Ring gear 70 79 Pinions:

The following various gear ratios were then obtained:

Reverse Forward Fifth l. 39 0 What I claim is:

1. In a transmission, especially for automobile vehicles, comprising a fixed frame, a movement input shaft, a movement output shaft, and a planetary gear train connecting said input shaft to said output shaft, said train having four elements of the type including a first element, control means by which said first element can be coupled to said movement input shaft or free; a second element, control means by which said second element can be coupled to said movement input shaft, or braked, or free; a third element permanently coupled to the movement output shaft; a fourth element, and control means by which said fourth element can be braked or free; said elements of said train meshing with each other to provide one reverse running condition and three forward running conditions which are low, intermediate and high; the elements of said train being arranged relative to each other such that for the reverse condition, the first element is coupled to the movement input shaft, the second element is braked and the fourth element is free; for the low forward condition, the first element is coupled to the movement input shaft, the second element is free and the fourth element is braked; for the intermediate forward condition, the first element is free, the second element is coupled to the movement input shaft and the fourth element is braked; and for the high forward condition, the first and second elements are coupled to the movement input shaft and the fourth element is free; the improvement wherein said control means of said first element comprise at least two clutches one of which when engaged while the other is disengaged defines a first connection path between said input shaft and said first element, and the other of which when engaged while the said one is disengaged defines a second connection path between said input shaft and said first element, gear means in at least one of said paths for establishing different ratios in both paths, and means for selectively placing either of said at least two clutches in driving relation between the movement input shaft and the first element thereby to vary on the one hand in the same direction the reverse ratio and the low forward ratio, and on the other hand, in the opposite direction, the high forward ratio of the planetary gear train.

2. A transmission as claimed in claim 1, in which said control means for said first element includes means for braking said first element so as to obtain an overdrive ratio, for which the first element is braked, the second element is coupled to the movement input shaft, and the fourth element is free.

3. A transmission as claimed in claim 1, and a reversing brake cooperating with said second element to brake said second element in order to obtain reverse gear ratios,

References Cited UNITED STATES PATENTS 3,152,491 10/1964 Wiggermann 74740 3,285,100 11/1966 Peltner et a1 74-688 2,844,975 7/1958 Kelbel et al. 74759 2,871,726 2/ 1959 Kamlukin 74740 X 2,886,984 5/1959 Whelpley 74759 3,255,642 6/ 1966 Christensen et al. 74-759 X ARTHUR T. MCKEON, Primary Examiner U.S. Cl. X.R. 74-740, 759

Patent No. 3,505,905 April 14, 1970 Pierre Andre Georges Lepelletier It is certified th patent and that said L shown below:

at error appears in the above identified etters Patent are hereby corrected as In the heading to the ,5 printed specification, line 8, "'Aug. 16, 1966"" should read Aug. 19, 1966 Signed and sealed this 1 6th day of February 1971.

(SEAL) Attest:

Edward M. Fletcher, Jr.

WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents 

